Expression device for pianos.



J. P, HULDER.

EXPRESSION DEVICE FOR. PIANOS.

APPLICATION FILED NOV. 26, 1909.

1,000,174. Patented Aug. 8, 191 1.

COLUMBIA PLANOGRAPH CO-. WASMNGTON. D r

TTNTE STATE T GFFTGE.

JOSEPH P. HULDER, OF NEJV YORK, N. Y., A$SIGNOB TO LUDWIG 8? COMPANY, .A CORFOEATION OF NEVV YORK.

EXPRESSION DEVICE FOR PIANOS.

To all whom itmay concern:

Be it known that I, Josnrrr P. HULDER, a citizen of the United States, and a resident of New York, in the county and State of New York, have invented certain new and useful Improvements in Expression Devices for Pianos, of which the following is a full, clear, and exact specification.

My invention relates to improvements in expression devices for pianos or pneumatic player pianos, and particularly to means for pneumatically controlling the force of the hammer blow upon the string so as to modulate the sound produced thereby.

The principal objects of my invention are to provide pneumatic means of novel construction for moving the hammer rest toward the strings, and valve means cooperative therewith for controlling the pneumatic means, whereby the position of the hammer rest may be shifted nearer to the strings to adjust the force of the hammer blow in varying degrees of intensity. Vl ith a constant power applied to the hammer, the volume of sound of the note struck will be governed by the distance through which the hammer strikes and consequently, by mov ing the hammer rest from its normal position, the notes may be played softer or louder at the will of the operator.

In the accompanying drawings, forming a part of this application, Figure 1 is a view in section of the expression pneumatic, showing a diagrammatic connection of the control valve; Fig. 2 is a front elevation, partly in section, of the control valve; and Fig. 3 is a view in perspective of a part of the control valve.

The drawings show my invention applied to a portion of the hammer action of a piano having strings (A), hammers (B), and a hammer rest rail (0).

(D) represents a suitable puppet valve board or casing disposed within the instrument below the hammer rest rail.

(E) represents a pneumatic attached to the under surface of the valve board and having arranged in the interior thereof a plate or board (1) hinged to the stationary part at (2), and to the movable leaf at (4:), so as to divide the pneumatic trans- Speeification of Letters Patent.

Application filed November 26, 190E).

Patented Aug. 8, 1911.

Serial No. 529,964.

versely into two independently collapsible sections (5-5). This valve board (D) is provided with the channels '-6), each separately connecting one section of the pneumatic to one of the puppet valves (77). These puppet valves are carried on diaphragms (S8) and are adapted to establish communication bet-ween one of the collapsible sections and the atmosphere or the exhaust chamber (9) alternatively through the ports or valve seats (1010') or (11-11) respectively, so as to operate that is, close or opensaid collapsible section.

The exhaust chamber (9) is normally maintained in a state of air tension by means of the usual suction bellows (not shown) or other suitable apparatus. The diaphragm chambers (12*12) are also normally maintained in a state of air tension through the usual bleed duct communication with the exhaust chamber. Tubes (13-13) leading to the diaphragm cham bers are shown to represent diagrammatically the connection of these chambers with the control valve means The hammer rest rail (C) is normally in the position shown. To shift the posi tion of the hammer rest nearer to the strings on the closing of the sections of the pneumatic, I provide the movable leaf of the pneumatic with the lever (14;) which is connected through a pitman (15) to an arm (16) secured to the hammer rest rail. It will be seen from this arrangement that as the sectional pneumatics are closed, the descending movement of the lever will throw the hammer rest rail toward the strings. As the sections of the pneumatic are inflated, the hammers and hammer rest rail will of their own weight fall to their normal positions, consequently it is only necessary to impart to the pitman a positive motion on the downward stroke of the lever. This is accomplished by inserting the lower end of the pitman through an opening (17) in the lever and securing it from below by an adjustable button (18).

Pianos or players are usually provided with manually operated meanssuch as pedals and connecting linksfor shifting the position of the hammer rail to modulate the sound of the instrument. My construction permits of such manual means being used in the same instrument independently of and without hindrance from the pneumatic means described.

The control valve means comprise the valve seats (19 19) located adjacent to each other in a suitable part of the instrument and connected by the tubes (13 13) to the diaphragm chambers (12-12) re spectively, and the flat spring members (2020) seated normally on the under surface of the parts (1919). The members (2020) are rigidly fastened at their rear ends (21) to the frame of the instrument. The member (20) is provided with a laterally projecting bent arm (22) which is adapted to engage the surface of the adjacent member (20) when the first member is depressed. A push button (2 1) and a hinged rod (23) are provided to depress the spring members.

I prefer to make the member (20) of relatively heavier material than the member (20) so that when the arm borne by the latter member engages the surface of the former member, the increased resistance against further depression may be readily felt by the operator.

It will be understood by those skilled in the art that the hammer rest rail may be suitably divided so as to modulate the bass and treble separately, in which event a second pneumatic and control valve should he provided.

It is also clear that the construction and arrangement of the various parts may be modified from that illustrated in the accompanying drawings without departing from the essential features of this invention; and furthermore, that a part or parts of this device may be used independently of the others.

The manner in which my device operates is as follows: By depressing the member (20) the valve seat is opened and air is admitted through the tube (13) to the dia phragm chamber (12) to raise the puppet valve (7) and exhaust the air from the section (5) of the pneumatic. This closing of the section draws the hammer rest rail toward the strings and carries the hammers in position for a blow of medium strength. On depressing the member (20) further, the projecting arm thereof will engage the surface of the member (20) depressing this member and causing its valve seat to be opened to the atmosphere so that in a corre sponding manner section (5) will be closed and thus move the hammer rest rail and the hammers to a position still nearer the strings for a soft blow.

It will be seen that by this device three degrees of intensity of the hammer blow may be obtained viz: from the normal nosition of hammer rest, from the intermediate position when the member (20) is depressed, and from the extreme position when both members (2020) are depressed.

I am aware that pneumatically operated devices have hitherto been invented to accomplish the modulation of sound by moving the hammer rest rail, or its equivalent nearer to the strings than in its normal position; but none of these devices, so far as I know, permit of as wide a range of modulation as may be attained with my device. Furthermore, I believe the sectional pneumatic and the control valve used in my device, as well as several other parts and combinations claimed herein, are entirely new (to the art.

What I claim as my invention and desire to secure by Letters Patent is:

1. In an expression device for pianos the combination with the strings, hammers, and hammer rest member of, a pneumatic having a plurality of independently collapsible sections; means actuated by the pneumatic for moving the hammer rest member toward the strings; and manually operated valve means for serially controlling the operation of the pneumatic sections.

2. In an expression device for pianos the combination with the strings, hammers, and hammer rest member of, a pneumatic having a plurality of independently collapsible sections; pneumatically operated valve means for alternatively opening and closing said sections; means actuated by the pneumatics for moving the hammer rest member toward the strings; and manually operated valve means for serially controlling the operation of the pneumatic sections.

8. In an expression device for pianos the combination with the strings, hammers, and hammer rest member of, a pneumatic comprising a stationary .wall, a movable wall, a member disposed within the pneumatic hinged to its stationary and its movable .walls dividing said pneumatic transversely into two independently collapsible sections; means actuated by the pneumatic for moving the hammer rest member toward the strings, comprising a lever arm borne by the movable wall, an arm secured to the hammer rest member, and connecting links; pneumatically operated valve means for alternately opening and closing said sections; and manually operated valve means for serially controlling the o eration of the pneumatic sections.

1. In an expression device for pianos the combination with the strings, hammers, and hammer rest member of a pneumatic comprising two independently collapsible sections; pneumatically operated valve means for alternatively opening and closing said sections; means actuated by the pneumatic for moving the hammer rest member tothe other member whereby, at the will of the Ward the strings and manually actuated operator, both members may be operated to- Valve means for controlling the pneumatic gether.

valve means, comprising two valve members JOSEPH P. HULDER. one of Which may be independently oper- Witnesses:

ated, and means borne by said independ- JOHN M. SGHULZE,

ently operated member adapted to engage BERTHA SIMoNY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

